Methods of varying the frequency to produce predetermined electrorheological responses

Abstract

Disclosed are electrorheological fluids including vermiculite treated with an amine salt, methods of making the same, propylene carbonate adsorbed on the solid phase, butyl benzoate added for the liquid phase, and methods of using frequency response of electrorheological fluids to vary apparent viscosity and to compensate for temperature.

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows: 
     
       1. A method of maintaining a substantially constant level of apparent viscosity of an electrorheological fluid under the influence of an alternating electric current field at substantially constant field strength comprising varying the frequency of the field to compensate for variations in temperature of the fluid and so that the apparent viscosity of the fluid is substantially constant. 
     
     
       2. A method of maintaining a substantially constant level of apparent viscosity of an electrorheological fluid under the influence of an alternating electric current field at substantially constant field strength comprising increasing the frequency of the field to compensate for increases in fluid temperature and so that a substantially constant apparent viscosity is maintained. 
     
     
       3. A method maintaining a substantially constant level of apparent viscosity of an electrorheological fluid under the influence of an alternating electric current field at substantially constant field strength comprising decreasing the frequency to compensate for decreases in temperature of the fluid and so that a substantially constant apparent viscosity is maintained. 
     
     
       4. A method maintaining a substantially constant apparent viscosity of an electrorheological fluid comprising amine-treated vermiculite particles in a silicone oil, which is under the influence of an alternating electrical current fluid at substantially constant strength comprising varying the frequency of the field between about 5 to about 5000 Hz to compensate for variations in temperatures ranging from about 0 to about 150° C. of the fluid and so that the apparent viscosity of the fluid is substantially constant.